Pass @extra to suggested option component

[AndreJoaquim]

Hello! 👋

I have a use-case where I'd like to have a power-select-with-create-suggestion component, to use in all of my invocations of <PowerSelectWithCreate>. Nevertheless, I'd like to change the message in this component. For this, it'd be helpful if the @extra argument would also be passed to the <SuggestedOption> component.

The ember-power-select documentation states the following:

[extra is an] Object to store any arbitrary configuration meant to be used by custom components

The description seems that this argument can solve this problem easily :) What do you think? If you're happy with it, I can open a pull request with the (simple) addition.